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The Influence of Limestone Powder and Metakaolin Co-Blending on the Hydration Process and Mechanical Properties of Q-Phase Cement

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1169-1176页

作者： XIONG Xuan he yongjia LÜLinnü MA Jie WANG Fazhou State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics School of ScienceWuhan University of TechnologyWuhan 430070China China Railway Design Corporation Tianjin 300250China

A ternary system comprising Ca_(20)Al_(26)Mg_(3)Si_(3)O_(68)(Q-phase),limestone,and metakaolin is proposed,and its hydration behavior,hydration product phases,microstructure,and mechanical properties are investigated and compared with pure Q-phase *** results indicate that the ternary system exhibits exceptional and sustained compressive strength even under a 40℃environment,significantly outperforming pure *** mechanism lies in that metakaolin effectively inhibits the transformation of metastable ***,the interactions among Q-phase,limestone,and metakaolin further enhance the cementitious *** ternary system effectively addresses potential issues of strength loss in Q-phase cement application,and as a low-carbon cementitious material system,it holds promising potential applications.

关键词： Q-phase limestone metakaolin hydration compressive strength

Effect of Calcium Carbonate Whisker on Impact Toughness of Precast Concrete

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Journal of Wuhan University of Technology(Materials Science) 2021年第3期36卷 374-380页

作者： LV Linnv WANG Yisa he yongjia WANG Fazhou HU Shuguang School of Science Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate Materials for Architec-tures(Wuhan University of Technology) Wuhan 430070China School of Materials Science and Engineering Wuhan University of Tech-nologyWuhan 430070China

The impact toughness and compressive strength of concrete added with calcium carbonate whisker are *** is found that calcium carbonate whisker can significantly improve the impact energy consumption at failure of 55℃steam cured concrete,but has limited impact on 90℃steam cured *** the same time,SEM,XRD and LF-NMR were used to study the micro morphology,hydration product components and pore structure of the concrete,and the mechanism of the influence of calcium carbonate whisker on the impact toughness and compressive strength of concrete was analyzed.

关键词： calcium carbonate whisker concrete products impact toughness compressive strength

Effects of Steam Curing on the Resistance of Cementitious Materials to Chloride Penetration

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Journal of Wuhan University of Technology(Materials Science) 2022年第5期37卷 885-891页

作者： CheN Xuefei he yongjia Lü Linnü ZHANG Xulong HU Shuguang State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan430070China Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics School of ScienceWuhan University of TechnologyWuhan430070China Hubei Provincial Academy of Building Research and Design Co. LtdWuhan430071China

The resistance to chloride penetration of cement-based material with different curing regimes was investigated by solution titration,XRD,LF-NMR and rapid chloride migration *** results show that the curing regime has influences on the types and structure of the hydration products,which in turn affects their ability to bind chloride *** binding capacity of cementitious materials to chloride ions,porosity and chloride ion migration coefficient increased with the increase of water-cement ratio,while steam curing increased the porosity and chloride ion migration coefficient at the same time as it increased the chloride ion binding capacity of the *** lower water-cement ratios,the effect of steam curing on the resistance of cementitious materials to chloride ingress is negligible.

关键词： chloride penetration chloride binding capacity pore structure steam curing cementitious materials

Effect of High Content Limestone Powder on Microstructure and Mechanical Properties of Cement-based Materials

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Journal of Wuhan University of Technology(Materials Science) 2023年第3期38卷 557-566页

作者：陈梦梦何永佳吕林女 ZHANG Xulong State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics School of ScienceWuhan University of TechnologyWuhan 430070China Hubei Provincial Academy of Building Research and Design Co. LtdWuhan 430071China

Compared with the control sample without limestone powder(LP), the mechanical properties of the sample with 30% LP can be significantly improved by using a small amount of water reducer to reduce the water-cement ratio, without significantly affecting the fluidity of the fresh mixture and increasing the economic cost. In addition, compared with the sole addition of limestone powder, dual addition of metakaolin and limestone powder can effectively improve the strengths. The reason of this phenomenon was investigated by means of XRD, TG-DTG, SEM, LF-NMR and isothermal calorimetry, etc. The reactive aluminum-rich phases in metakaolin react with limestone powder in the hydration process, and the formed calcium carboaluminate reduces the porosity and makes the hardened paste denser. The addition of ground granulated blast furnace slag can also improve the strength of the specimen added with limestone powder, whereas, the effect is inferior to that of metakaolin, for the ground granulated blast furnace slag contains less reactive aluminate phases, and accordingly, the amount of calcium carboaluminate generated is lower than that of metakaolin.

关键词： limestone powder aluminum-rich phase mineral admixture calcium carboaluminate

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利用废弃混凝土制备再生胶凝材料

硅酸盐学报 2007年第5期35卷 593-599页

作者：胡曙光何永佳武汉理工大学硅酸盐材料工程教育部重点实验室武汉430070

为了提高废弃混凝土再生资源的利用效率,提出实现各组分高效再生利用技术路线和方法。将分离出来的水泥石组分经过低温煅烧处理,制备得到可再次水化并形成胶凝能力的再生胶凝材料。利用X射线衍射、扫描电子显微镜、力学测试等手段对其... 详细信息

为了提高废弃混凝土再生资源的利用效率,提出实现各组分高效再生利用技术路线和方法。将分离出来的水泥石组分经过低温煅烧处理,制备得到可再次水化并形成胶凝能力的再生胶凝材料。利用X射线衍射、扫描电子显微镜、力学测试等手段对其矿物组成、水化硬化过程等进行了研究。实验结果表明:不同煅烧温度下制备得到的再生胶凝材料矿物组成及其结构不同,使其水化活性存在差异。其中在650℃煅烧得到的再生胶凝材料以不完全结晶的β-C2S矿物相为主要成分,具有优良的水化胶凝能力。

关键词：废弃混凝土再生资源回收利用再生胶凝材料

水泥石脱水相结构特征及其再水化能力(英文)

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硅酸盐学报 2008年第10期36卷 1343-1347页

作者：吕林女何永佳胡曙光武汉理工大学理学院硅酸盐材料工程教育部重点实验室武汉430070

将水泥石在不同温度进行低温煅烧,得到不同的脱水相物质,通过热重–差示扫描热分析、X射线衍射、红外光谱及29Si核磁共振等对水泥石在400,650℃及900℃的脱水相结构特征及其再水化性能、再水化产物的结构特征进行研究。结果表明:在400℃... 详细信息

将水泥石在不同温度进行低温煅烧,得到不同的脱水相物质,通过热重–差示扫描热分析、X射线衍射、红外光谱及29Si核磁共振等对水泥石在400,650℃及900℃的脱水相结构特征及其再水化性能、再水化产物的结构特征进行研究。结果表明:在400℃,由水化硅酸钙(C–S–H)凝胶脱水生成了无定形相,在650℃生成了不完全结晶的β-硅酸二钙(C2S),而900℃脱水相中存在结晶程度高的β-C2S。在再水化过程中,400℃和650℃脱水相水化生成了C–S–H凝胶,并且650℃脱水相的水化活性和水化产物聚合程度更高;900℃脱水相的水化活性极低,水化前后矿物结构特征几乎没有发生变化。

关键词：水泥石脱水相结构特征:再水化水化活性

用^(27)Al MAS NMR分析铝掺杂水化硅酸钙结构中铝的配位状态（英文）

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硅酸盐学报 2017年第8期45卷 1096-1100页

作者：吕林女何永佳何满倩胡曙光武汉理工大学理学院武汉430070 武汉理工大学硅酸盐建筑材料国家重点实验室武汉430070 武汉理工大学材料科学与工程学院武汉430070

制备了具有宽范围Ca/(Si+Al)比和Al/Si比的铝掺杂水化硅酸钙(C-A-S-H)系列样品,采用^(27)Al魔角旋转固体核磁共振技术(^(27)Al MAS NMR)半定量研究了Al在C-A-S-H结构中的配位状态。结果表明:Al在C-A-S-H结构的配位形式和位置主要取决于... 详细信息

制备了具有宽范围Ca/(Si+Al)比和Al/Si比的铝掺杂水化硅酸钙(C-A-S-H)系列样品,采用^(27)Al魔角旋转固体核磁共振技术(^(27)Al MAS NMR)半定量研究了Al在C-A-S-H结构中的配位状态。结果表明:Al在C-A-S-H结构的配位形式和位置主要取决于其初始Ca/(Si+Al)比和Al/Si比。当初始Ca/(Si+Al)比低时(0.6和0.8),Al只能取代硅酸盐链硅氧四面体结构中四配位的Si,以Al[4]的形式存在;随着Ca/(Si+Al)比的增加,部分Al开始形成Al[5]和Al[6],且随着Al/Si比的增加,Al[4]的含量减小,Al[5]和Al[6]的总量增加,但Al[4]还是占主要比例,Al[5]的量非常少。Al[4]既可取代桥四面体中的Si也可取代配对四面体中的Si,但优先取代的是桥四面体中的Si,两者取代比并非恒定,而是随着初始Ca/(Si+Al)比和Al/Si比的变化而变化。

关键词：结构铝取代水化硅酸钙 ^27Al魔角旋转固体核磁共振技术

基于微米划痕的水泥基材料断裂韧性测试与分析方法

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硅酸盐学报 2022年第2期50卷 452-456页

作者：姚顺胡传林何永佳王发洲硅酸盐建筑材料国家重点实验室武汉理工大学武汉430070 武汉理工大学材料科学与工程学院武汉430070

水泥基材料脆性突出、易开裂是其工程应用亟须解决的关键难题。对水泥基材料各物相的微观脆性进行解析,并建立与其水泥基材料整体脆性之间的联系,是对水泥基材料进行增韧设计的基础和关键。采用微米划痕实验,获得断裂韧性-位移曲线,并... 详细信息

水泥基材料脆性突出、易开裂是其工程应用亟须解决的关键难题。对水泥基材料各物相的微观脆性进行解析,并建立与其水泥基材料整体脆性之间的联系,是对水泥基材料进行增韧设计的基础和关键。采用微米划痕实验,获得断裂韧性-位移曲线,并联合高分辨扫描电子显微镜分析划痕区域所对应的物相,实现了水泥浆体及其微观物相断裂韧性的定量表征,从而建立了水泥浆体整体脆性与水化硅酸钙凝胶脆性之间的联系。

关键词：微米划痕水化硅酸钙断裂韧性水泥基材料

Binding Materials of Dehydrated Phases of Waste Hardened Cement Paste and Pozzolanic Admixture

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Journal of Wuhan University of Technology(Materials Science) 2009年第1期24卷 140-144页

作者：吕林女 School of Science Wuhan University of Technology

Fly ash （FA） and ground granulated blast-furnace slag （GGBFS） were added to improve the performances of regenerated binding materials （RBM） which refer to dehydrated phases with rebinding ability of waste hardened cement paste. Flowability tests, compressive strength tests, SEM, TG-DSC, and non-evaporable water content tests were employed to study the performances of the combined binding materials and the interactions between RBM, FA, and GGBFS. Results show that adding FA or GGBFS can improve the workability of RBM paste, and GGBFS has positive effects on strength of RBM. Pozzolanic reactions happen between RBM, FA, and GGBFS. And the activation effect of RBM to FA and GGBFS is superior to that of P.O grade-32.5 cement, especially at earlier ages, because of the high reactive f-CaO existing in RBM. On the advantages of the synergetic effects of RBM and pozzolanic admixtures such as FA and GGBFS, new combined binding materials can be prepared by blending them together.

关键词： combined binding materials dehydrated phase fly ash granulatedblast-furnace slag